Jaundice associated with breast feeding is a frequent problem facing the paediatrician. Despite numerous reports on this subject, the natural history, familial occurrence and late neurodevelopment of children with breast milk jaundice remain unclear. The follow up of 60 infants with breast milk jaundice showed that there are two bilirubin peaks, on the 4th and 5th day and on the 14th-15th day of life. In the infants with uninterrupted breast feeding, the hyperbilirubinaemia disappeared slowly and could still be detected 12 weeks after birth. The familial incidence of 13.9%, indicating that in some cases a unique genetic factor is expressed. Late neurodevelopment or hearing defects were not observed, thus enabling the paediatrician to encourage continuation of breast feeding in most cases of healthy infants with breast milk jaundice.